The present invention relates to a device for instantaneous fixing in accordance with safety standards for various parts of elongated shape and in particular for bending tools which are intended to be fixed on the platen of a bending-press.
By way of example, the tool can be a bending-press punch or die which is securely attached or fixed to the platen or to one or a number of intermediate tool-holders. The tool must be adapted to operations performed on the bending-press and therefore has to be changed at frequent intervals.
In the majority of instances, the tool has a heel applied against a vertical face of the tool-holder by means of clamps and a plurality of screws. When it is suspended, the tool must be prevented from falling in the event of slackening-off. To this end, the heel can be provided with a grooved or shouldered portion whilst the clamps have an inverse shape. In this case, the heel can be mounted or extracted only laterally by sliding, which is subject to disadvantages, in particular when other tools are located on each side of the tool to be changed.
Moreover, the time required to tighten-up all the screws is considerable. As a palliative measure, the screws can be replaced by hydraulic or pneumatic systems as described in French Pat. No. 2 339 485 and German Pat. No. 35 24 694. This does permit a saving of time in the tightening operation but does not overcome the difficulties involved in extraction of the tool. In addition, these devices are expensive and exacting in their requirements since they have to meet strict safety standards in order to guard against the danger of falling as a result of accidental leakage of fluid.
For the reasons just given, the present invention is intended to provide a tool-fixing device which offers every guarantee of operational safety, which permits front introduction in the position of attachment and which ensures instantaneous clamping by means of a simple movement exerted by the operator in order to tilt the tool to its work position, thus initiating automatic locking of the clamping member as a result of this movement.